that sounds potentially useful for 0G
https://www.fsfla.org/~lxoliva/#0G

one could get essentially infinite range with enough density, very much like the OLPC vision of mesh-networked laptops.

alas, but most phones' radios are fundamentally proprietary and thus hostile to users, to freedom, and to repurposing :-(

but something like this might make it worth the effort to reverse engineer them and reprogram them